pcm42222evm

[EEMO1]

there's a topic about the pcm42222evm at gearslutz:


http://www.gearslutz.com/board/geek...cook-best-class-2-ch-pre-amp-d-convertor.html


i have to admit, i got a little interested. what's the deal with the board?

 

[12afael]

where is Rochey??? :razz:

 

[SSLtech]

Traveling... -and right there in that thread.

Keith

 

[living sounds]

Do a search here! Someone posted along the lines of "it was good but it didn't blow me away, tried a Prism, that one blew me away". Bottom line: Good converter for the money I guess. Still, at least for people in euroland a Black Lion Sparrow might be the better deal.

 

[Rochey]

Gents,

forgive the short answer, I've got to leave soon for a meeting.

The PCM4222 Eval board is not really something I would consider for a "rack-up" project. The reason for this is:

- It has no word clock input. The clock input is for it's master clock only. That means that in any recording system, the eval board would have to be the clock master.

- You'll need an external power supply board.

- The front end gain circuitry has been optimised for a large input swing from an audio precision tester. If memory serves, the maximum input (Full Scale) is up at 27Vpp.

If I was going to do my own rack product with the PCM4222, I would look at the ADC card for the Focusrite ISA828. It's a separate card that you can buy for the ISA828, but has 8 analog input, word clock I/O, Adat Out and multiple S/PDIF outs.

http://www.sweetwater.com/store/detail/ISA828Card/

/R

 

[EEMO1]

thanks for the answers everyone!

i wasn't actually that far off with my own conclusions... i guess people got a little bit nuts over at gearslutz.


rochey, thanks for the focusrite tip. i guess someday i'll do a project with that in mind.

 

[mikep]

[quote author="living sounds"]Do a search here! Someone posted along the lines of "it was good but it didn't blow me away, tried a Prism, that one blew me away". Bottom line: Good converter for the money I guess. Still, at least for people in euroland a Black Lion Sparrow might be the better deal.[/quote]

Yeah, that was my comment. I am still using the 4222 from time to time even though I own the Prism. I am using this in a mastering room, I always capture at 44.1, and never need more than 2 channels, so the wordclock limitation is not an issue. The low end on the TI is notworthy. Hard to describe... extended, big, and very uncolored. clipping the 4222EVM is disgusting. It doesnt flat-top, it goes silent for a few ms then recovers. IMO a proper implementation of this chip would address input limiting. FWIW I had no problem generating input signals that would clip, but the line amp that drives the A/D in my setup has headroom from hell.

Were there any subjective opinions at gearsluts?

mike p

 

[Jidis]

Sorry to bump this back from the dead, but I've recently purchased one of these.

As it ships with jacks and all pre-installed on both sides, did they have some standard enclosure type in mind? If so, where might it be? If not, and I try to track down something large enough, is plastic a bad idea with regard to shielding? I'm trying to avoid a full sized rack box, as I'd like to use it for portable tests of mics,etc., but if I end up needing to go with an internal PSU, it may be too close to rack size anyhow.

Thanks! 

 

[Rochey]

Eval boards are not designed to go into enclosures. They are designed for product designers to evaluate on the workbench, then design their own systems.

How do you plan to lock to other systems? That board does not support wordclock.

 

[Jidis]

Hi Rochey (I was hoping you'd see this),

Yeah, I read up on the board long long ago and know what it was intended for and all, I just figured since they installed big heavy jacks on it, that maybe there was something out there to protect it 'as is'.

Re: clock - The EVM will be master any time I use it.

I have a feeling I'm going to end up with something close to rack size though on the case. I'm thinking now that I'd rather not have a power brick tied to it if I can get a low profile transformer in there. I'm also going to be looking into some sort of USB/I2C board or something to keep from having to use an additional interface box when I'm not around AES/SPDIF stuff.

I do need to go back and refresh my memory on the EVM and what it allows though.

-Thanks!

George

 

[Rochey]

Good luck! Sorry if I came accross a little harsh...
People seem to thinkt hat the EVM is a system, and it really isn't.
Things like ESD protection weren't done. the full scale voltage is enormous on the board so that the AP can measure it's performance.

 

[Jidis]

This thing is scary close to the size of my Symetrix SX202. I see what you're saying on their intentions though. It doesn't even have holes in the corners (at least not ones which aren't filled).

George

 

[rafafredd]

Does Anyone has the Focusrite card pinouts???

 

[therecordingart]

Bumping an old thread. Does anyone have the focusrite card pinout?